Space heater

ABSTRACT

A space heater comprises a housing ( 4 ) having a rear wall ( 8 ) and a front wall ( 10 ). Located forwardly of the front wall is a solid fuel effect means ( 12 ). Heating means is provided, in conventional manner. Suspended within the housing ( 4 ) by an upper support ( 30 ) is a flame effect means which in a preferred embodiment is in the form of a sheet of lightweight flexible material, the sheet being provided with elongate openings ( 20 ). Means ( 18 ) is provided to cause the sheet ( 14 ) to move, specifically by directing a flow of air upwardly against the material, to cause the material to billow. Light is directed from a light source ( 28 ) against the flame effect means, some light being reflected from the flame effect means directly through a translucent screen ( 24 ), some light passing through openings ( 20 ) of the sheet ( 14 ) onto a reflector ( 32 ), and being reflected from the reflector back through the sheet ( 14 ), and through the screen ( 24 ).

DESCRIPTION OF INVENTION

This invention relates to space heaters, and particularly but notexclusively to apparatus for simulating flames in a solid fuel effectfire, to give the impression of flames emanating from combusting fuel.

A conventional space heater, herein referred to as being of the kindspecified, comprises a housing, heating means in the housing, a flameeffect means in the housing, a source of light to illuminate the flameeffect means in the housing, and a screen through which light istransmitted from the housing. Frequently a means is provided, such as bya fan or mechanical means, to cause the flame effect means to move inthe housing, and frequently the screen is translucent, to make thevisual effect produced within the housing somewhat diffuse.

Several arrangements have been used in the past to simulate flames inapparatus of the kind specified. For example, in GB-A-968568, there isshown an apparatus in which the flame effect means comprises a pluralityof reflective ribbons suspended adjacent to a rear part of the fire, thelight source being located forwardly of the ribbons, with a translucentscreen also being located forwardly of the ribbons, such that light fromthe light source reflected from the ribbons is incident on a rear faceof the screen, giving a flame effect when the screen is viewed from thefront.

As another example, it is known from GB-A-1186655 to suspend the ribbonsin front of the light source, so that light is transmitted between thestrips directly onto the translucent screen.

In the specification of our European patent specification EP 0986722-A,the flame effect means is in the form of a sheet of translucentmaterial, such as crepe-de-chine, which is provided with a plurality ofvertically-extending elongate slits, the material being locatedoptically between the light source and the screen. A fan within thehousing causes the material to billow, and the slits periodically toopen a short distance, allowing light to be transmitted directly ontothe screen, thus simulating a flame.

It has been appreciated by the present inventor, that in the past theprimary attention has been directed towards producing relatively highlevels of light falling on the screen, and that this has not beenparticularly conducive to producing a high quality simulated flame.

Conversely, and in accordance with this invention, there is provided aspace heater characterised by the feature that light is directed fromthe light source through the flame effect means onto a reflector, andreflected light passes again through the flame effect means onto thescreen.

Preferably the flame effect means comprises a sheet of flexiblematerial, and is preferably generally matt, producing only a low levelof reflected light. For example, the flame effect means may be providedby a sheet of silky material, such as crepe-de-chine, preferably beingof a dark colour, such as dark red, or even black.

Preferably the flame effect means provides openings, means beingprovided to cause the flame effect means to move in the housing therebycausing the openings to move.

Preferably the openings which are provided in the sheet are elongate,and the material is suspended loosely within the housing, being causedto “billow” by the flow of air directed there across, or by mechanicalmeans. Such billowing will cause the slits to open, and for theseopenings to be seen to travel vertically in the upwards direction, or ifdesired, downwardly.

Light passing through the screen will be provided at four levels, asfollows:

-   -   a) light which passes from the source through the material of        the flame effect means to the reflector and from the reflector        back through the material of the flame effect means onto the        screen;    -   bi) light which passes from the source through an opening in the        material of the flame effect means to the reflector and through        the material onto the screen;    -   bii) light which passes through the material onto the reflector        and onto the screen via the material of the flame effect means;    -   c) light reflected from the flame effect means directly onto the        screen;    -   d) light passing from the source through one of the openings        onto the reflector, and from the reflector back through one or        other of the openings onto the screen.

Conveniently, levels a) and b) may be maintained at a low, ineffectivelevel, whilst the level c) is sufficient only to provide a low levelbackground glow.

Light at level d) will be intermittent, but at a relatively high level,providing a “smoky” flame effect which may achieve a high level ofrealism.

By varying the thickness and colour of the material which provides theflame effect means, and by varying the thickness of the slits, thecolour and power of the lamp, and the degree of fogging on the screen, ahigh quality flame effect means may be produced over a wide range ofvisual outputs.

Alternative to the use of the flame effect means being provided by asheet of flexible material, the flame effect means may comprise aplurality of ribbons.

There will now be given a detailed description, to be read withreference to the accompanying drawings, of a space heater which is apreferred embodiment of this invention, having been selected for thepurposes of illustrating the invention by way of example.

In the accompanying drawings:

FIG. 1 is a vertical sectional view of an electric fire which is thepreferred embodiment of this invention;

FIG. 2 is a schematic perspective view, illustrating principles ofperformance of the fire; and

FIG. 3 is an enlarged view illustrating the production of “openings” inthe flame effect means.

The space heater which is the preferred embodiment of this invention isan electric fire, comprising a housing 4 having a base 6 and a rear wall8. Located forwardly of the front wall 10 an illuminated coal effect 12may be provided, in conventional manner. Heating means (not shown) isalso provided, in conventional manner.

Suspended within the housing 4 from an upper support 13 is a sheet 14 ofa lightweight flexible material, such as crepe-de-chine, said sheetbeing secured loosely by lower securing means 16, adjacent a lower endof the housing.

Mounted adjacent to the lower securing means 16 is a fan 18 arranged todirect a flow of air upwardly against the material 14, to cause thematerial to billow in an upward direction, and if desired, the lower endof the sheet may be secured to a rear wall of the fan housing.

As is seen from FIG. 2, provided in the sheet 14 are a plurality ofslits 20, said slits extending a majority of the height of the sheet 14,and being generally parallel to the side edges of the sheet, there beingin the preferred embodiment perhaps sixteen such slits disposeduniformly width-wise of the housing 4.

Extending upwardly to an upper closure member 21 is a translucent screen24, conveniently of perspex or glass.

Provided within the housing 10 adjacent a front face of the sheet 14 isa light source 28, arranged to direct light against the front face ofthe sheet 14, conveniently the light source simultaneously providing anillumination for a solid fuel (wood or coal) effect element 12.

Under the influence of the current of air directly upwardly across thesheet 14, the slits form openings 21 (see FIG. 3), which move generallyin the upwards direction as the sheet billows under the influence of theflow of air. However, alternatively the air flow may be directeddownwardly, to cause the openings 21 to move in the downward direction.Light directed against the sheet 14 in part passes through the materialitself, falling against a generally triangular reflector 32 mounted onthe rear wall 8 of the housing, light reflected therefrom passingforwardly through the sheet 14 and through the screen 24.

Some of the light transmitted against the sheet 14 will also passthrough the openings themselves in one direction of traverse of thesheet 14, whilst some light will pass through openings formed by theslits 20 in both directions of traverse of the light. This latter lightappears through the screen 24, and hence to a viewer of the space heateras areas 30 of light moving upwardly of the screen, quickly dissipatingdue to the lower degree of incidence of light from the source 28 on theupper parts of the reflector 32, and by virtue of the shape of thereflector itself, simulating flickering flames.

The level of the background glow which will be observed on the screen 24will primarily be produced by light being reflected from the front faceof the material 14 through the screen. The intensity of the backgroundglow will be determined in part of course by the colour of the materialof the sheet 14, and may, if desired, be enhanced by a reduction inthickness, so that there is a small contribution to the background glow,by light being reflected from the reflector 32, and passing through thematerial 14 itself.

It has been found that, where the material 14 is afforded bycrepe-de-chine which is black in colour, and the light source 14 isarranged to transmit a white light, a “smoky” flame effect is produced.Alternatively, a warmer effect may be produced, by the use ofcrepe-de-chine of a dark red colour, together with an orange light asthe light source 14.

Alternative to the use of the sheet 14 of crepe-de-chine, the flameeffect means may be provided by a plurality of ribbons, suspendedbetween the reflector and the light source in a manner such that lightpasses from the source 28 to the ribbons, some light being reflecteddirectly from the ribbons through the screen, other light passing theribbons and being reflected by the reflector 32, whereby light fallingon the screen is at a number of different levels. The ribbons may be oftranslucent material, such as crepe-de-chine, but may be partlyreflective.

In the present specification “comprises” means “includes or consists of”and “comprising” means “including or consisting of”.

The features disclosed in the foregoing description, or the followingclaims, or the accompanying drawings, expressed in their specific formsor in terms of a means for performing the disclosed function, or amethod or process for attaining the disclosed result, as appropriate,may, separately, or in any combination of such features, be utilised forrealising the invention in diverse forms thereof.

1. A space heater comprising a housing and flame effect means in thehousing, the flame effect means comprising a source of light toilluminate the flame effect means in the housing, and a screen throughwhich light is transmitted from the housing, characterised in that lightis directed from the light source through the flame effect means onto areflector, and reflected light passes again through the flame effectmeans onto the screen.
 2. A space heater according to claim 1 whereinthe flame effect means comprises a sheet of flexible material.
 3. Aflame effect means according to claim 2 wherein the sheet of flexiblematerial is provided by a sheet of silky material.
 4. A space heateraccording to claims 2 or 3 wherein the sheet of flexible material iscrepe-de-chine.
 5. A space heater according to claims 1, 2 or 3 whereinthe flame effect means is provided with openings.
 6. A space heateraccording to claim 5 wherein the openings are elongate.
 7. A spaceheater according to claims 1, 2 or 3 wherein the material providing theflame effect means is suspended loosely within the housing, and means isprovided to cause the material to “billow”.
 8. A space heater accordingto claim 1 wherein the flame effect means comprises ribbons, means beingprovided to cause the ribbons to move.
 9. A flame effect means accordingto claims 1, 2, 3 or 8 wherein light passing through the screen isprovided at a number of different levels.
 10. (Canceled)
 11. (Canceled)